Et al. is short for the Latin et alii, meaning “and others.” In a citation it stands in for the co-authors you don't list: (Okafor et al., 2022) tells the reader that Okafor and at least two other people wrote the work. Only al. takes a period, because et is a whole Latin word, and APA, MLA and Chicago all print it in regular type rather than italics.
When you switch from names to et al. depends on the style and on where the citation sits. APA 7 uses et al. in the text for three or more authors, from the first citation, but never in the reference list. MLA 9 uses it in both places. Chicago's 18th edition uses it in notes and author-date citations, while its bibliography lists up to six names. The table gives the rule for each style; the sections after it put an in-text citation next to its reference entry for each one.
Et al. rules at a glance
| Style (edition) | In the text or notes | In the reference list or bibliography |
|---|---|---|
| Style (edition)APA, 7th ed. (2019) | In the text or notes3+ authors: first author + et al., from the first citation | In the reference list or bibliographyNo et al.: list up to 20 authors; for 21 or more, the first 19, an ellipsis, then the last |
| Style (edition)MLA, 9th ed. (2021) | In the text or notes3+ authors: first author + et al. | In the reference list or bibliography3+ authors: first author + et al. |
| Style (edition)Chicago, 18th ed. (2024) | In the text or notes3+ authors: first author + et al. (notes and author-date citations) | In the reference list or bibliographyUp to 6 authors: list all. 7 or more: first three + et al. |
What et al. stands for
Latin has three plural forms for “others,” depending on grammatical gender: et alii (masculine), et aliae (feminine) and et alia (neuter). The abbreviation covers all three, so you never have to choose. Read aloud, it is usually said as written, “et al,” or simply as “and others.”
You'll also meet it in law, where a case caption can name the first party on each side and add et al. for the rest, as in a made-up caption like Garcia et al. v. Northfield School District.
In academic writing, et al. does one job: it keeps a long author list from taking over a sentence. A study by eleven researchers becomes “Okafor et al. (2022)” instead of a paragraph of surnames. Whether the full list appears anywhere depends on the style: APA's reference list names everyone up to 20 authors, while an MLA works-cited entry uses et al. too.
How to write et al. correctly
Most mistakes with et al. are about one period and one comma. These rules hold in APA, MLA and Chicago unless the style sections below say otherwise.
- One period, after al. Et means “and” and is a full word. Al. is short for alii, so it takes the period: et al. Not et. al., et. al or etal.
- No italics in APA, MLA or Chicago. APA's rule is that foreign words and abbreviations that appear in an English dictionary stay in regular type, and et al. does.
- No comma between one surname and et al. (Okafor et al., 2022) in APA, (Okafor et al. 112) in MLA. A comma does go before et al. when it follows more than one name or an inverted name: Okafor, Lena, et al. at the start of an MLA works-cited entry, or (Jones, Smith, Liu, et al., 2020) when APA needs extra names to tell two sources apart.
- Plural verbs. Et al. means “and others,” so the subject is several people: “Okafor et al. (2022) suggest,” not “suggests.”
- One period at the end of a sentence. If et al. ends the sentence, its period ends the sentence too: “The model was first tested by Okafor et al.” Never two.
- The possessive is et al.'s. “Okafor et al.'s (2022) survey” is grammatical, but “the 2022 survey by Okafor et al.” usually reads more smoothly.
- Et al. replaces at least two names. A two-author work keeps both names: (Okafor & Ruiz, 2022) in APA, (Okafor and Ruiz 45) in MLA.
Correct
- Okafor et al. (2022) suggest that sleep matters more than screen time.
- (Okafor et al., 2022)
- Okafor, Lena, et al. (start of an MLA works-cited entry)
- The 2022 survey by Okafor et al. found the same pattern.
- The method comes from Okafor et al.
Incorrect
- Okafor et. al (2022) suggest… (period on the wrong word)
- (Okafor, et al., 2022) (no comma between one surname and et al.)
- Okafor, Lena et al. (missing comma in MLA works cited)
- Okafor et al. (2022) finds… (verb should be plural)
- The method comes from Okafor et al.. (two periods)
Et al. in APA 7th edition
APA's 7th edition keeps et al. out of the reference list and puts it in every in-text citation of a work with three or more authors, including the first. Here is one three-author source in both places:
In the text: (Okafor et al., 2022) · Okafor et al. (2022) argue…
In the reference list: Okafor, L., Ruiz, D., & Tanaka, M. (2022). Sleep, screens and memory in the last year of school. Northfield Review of Education, 14(2), 101–118.
That split is the APA rule that's easiest to misread: et al. in the text, every name in the reference list. List up to 20 authors there, with an ampersand before the last. For 21 or more, list the first 19, then an ellipsis, then the final author, with no ampersand.
One and two authors are named in every citation: (Okafor, 2022) and Okafor (2022); (Okafor & Ruiz, 2022) in parentheses and Okafor and Ruiz (2022) in running text.
Two exceptions keep citations distinct. If two sources would shorten to the same form, say two 2020 papers by Jones, Smith and different co-authors, write out as many names as you need to tell them apart, then a comma and et al.: (Jones, Smith, Liu, et al., 2020) and (Jones, Smith, Ruiz, et al., 2020). And because et al. is plural, it can't stand for a single name: if only the last author differs, write out every name in every citation.
For a reference list with notes on each source, the APA annotated bibliography template keeps each reference and its annotation together.
Et al. in MLA 9th edition
MLA uses et al. in the works-cited list and in the text alike once a source has three or more authors. In the works-cited entry, invert the first author's name and add a comma before et al. In the text, it's the surname, et al., and the page number, with no comma at all.
In the text: (Okafor et al. 45) · Okafor et al. describe…
Works cited: Okafor, Lena, et al. The Tired Classroom. Northfield Press, 2022.
Two authors, for comparison: (Okafor and Ruiz 45) · Okafor, Lena, and Daniel Ruiz. The Tired Classroom. Northfield Press, 2022.
MLA writes “and” between two authors, never an ampersand.
Et al. in Chicago style
Chicago changed its thresholds in the 18th edition, published in 2024, so check which edition you've been asked to follow. Guides written for the 17th edition give different numbers, which is why advice online disagrees.
Chicago 18th edition (2024)
- Notes: for three or more authors, give the first author followed by et al.
- Bibliography: list up to six authors in full. For seven or more, list the first three followed by et al.: Okafor, Lena, Daniel Ruiz, Mei Tanaka, et al.
- Author-date: the same thresholds. In the text, three or more authors become (Okafor et al. 2022, 45); the reference list names up to six.
Note: 1. Lena Okafor et al., The Tired Classroom (Northfield Press, 2022), 45.
Bibliography: Okafor, Lena, Daniel Ruiz, and Mei Tanaka. The Tired Classroom. Northfield Press, 2022.
Author-date, in the text: (Okafor et al. 2022, 45)
Author-date, reference list: Okafor, Lena, Daniel Ruiz, and Mei Tanaka. 2022. The Tired Classroom. Northfield Press.
The 18th edition also stopped requiring a book's place of publication, which is why these entries have none.
Other styles set their own limits. Medical and engineering styles such as AMA and IEEE cite by number and have their own rules for long author lists, and Harvard style has no single official manual, so follow the version your journal or university gives you.
Et al. vs etc.
Both are Latin abbreviations that end a list early, and they're easy to mix up. The rule is short: et al. is for people, etc. is for things. Two cousins, e.g. and i.e., belong in the same table because they're confused with etc. so often.
| Abbreviation | Latin | Means | Use it for | Example |
|---|---|---|---|---|
| Abbreviationet al. | Latinet alii, aliae, alia | Meansand others | Use it forPeople: authors, editors, parties to a case | ExampleOkafor et al. (2022) |
| Abbreviationetc. | Latinet cetera | Meansand the rest | Use it forThings in a list | Examplepens, notebooks, index cards, etc. |
| Abbreviatione.g. | Latinexempli gratia | Meansfor example | Use it forIntroducing examples (don't add etc.) | Examplea citation style (e.g., APA) |
| Abbreviationi.e. | Latinid est | Meansthat is | Use it forRestating or narrowing | Examplethe main style (i.e., APA 7) |
In writing for a general reader, neither may be the best choice. “Lena Okafor and her colleagues” reads more naturally in a magazine piece than “Okafor et al.,” which signals an academic citation.
Practice: fix the citation
Each line has one mistake. The style is in brackets.
- (Okafor, et al., 2022) [APA 7]
- Okafor et. al (2022) argues that sleep comes first. [APA 7]
- (Okafor et al., 2022), for a book by Okafor and Ruiz [APA 7]
- Okafor, Lena et al. The Tired Classroom. [MLA 9]
- A bibliography entry that lists all eight authors of a paper [Chicago 18]
- The interviews were coded by Okafor et al.. [any style]
- (Okafor et al., 2022). No comma between one surname and et al.
- Okafor et al. (2022) argue that sleep comes first. Period after al., plural verb.
- (Okafor & Ruiz, 2022). Two authors are always both named.
- Okafor, Lena, et al. A comma goes before et al. after an inverted name.
- List the first three authors, then et al. Chicago 18 lists all names only up to six.
- …coded by Okafor et al. One period ends both the abbreviation and the sentence.
Check a paper before you submit
Search the paper for et al and check each hit against your style's threshold, the period after al. and a plural verb. Where the rule differs between editions, the style guide your instructor or journal names has the final word.
You can also ask the Strokes Assistant to review the paper for inconsistent author lists: et al. after a single co-author, a source named in full in one paragraph and shortened in the next, or a stray period after et.
Frequently asked questions
Is it et al or et al.?
In APA, MLA and Chicago it is et al., with one period after “al” and none after “et,” because et is a complete Latin word meaning “and” while al. is short for alii. Forms like et. al. and et. al put the period in the wrong place. If a journal's own guidelines say otherwise, follow the journal.
Do you italicize et al.?
Not in APA, MLA or Chicago, which all set et al. in regular type. APA's reasoning is that words and abbreviations of foreign origin that appear in an English dictionary are not italicized, and et al. is in the dictionary. If a journal's guidelines ask for italics, follow them.
Can you use et al. for two authors?
No. Et al. has to replace at least two names, so a two-author source always names both people: (Okafor & Ruiz, 2022) in APA parentheses, Okafor and Ruiz (2022) in running text, and (Okafor and Ruiz 45) in MLA. In APA 7, MLA 9 and Chicago's 18th edition, et al. starts at three authors.
Is et al. singular or plural?
Plural. Et al. means “and others,” so the subject refers to several people and takes a plural verb: Okafor et al. (2022) argue, report or found. Writing “Okafor et al. argues” treats a group of authors as one person. If the sentence sounds awkward, name the work instead: “The 2022 study by Okafor et al. found…”
